They identify which chokes you have in without having to use a choke tool. different companies have different markings but in general the fewer marks, the more constricted the choke (1 mark=full choke).
A choke, as it relates to firearms, is a narrowing of the end of the shotgun barrel. This narrowing can be greater or smaller. Chokes that are smaller than the bore to a greater degree are called...
Notches on the Choke TubeMost standard choke tubes have notches on their ends. The notches can be used to identity your choke tube, but they can be difficult to see. The following list shows what...